Reclosable cartons



Nov. 8, 1966 J. G. HUGHES RECLOSABLE CARTONS 2 Sheets-Sheet 1 Filed NOV. 9, 1964 INVENTOR JOHN G. Hue/15s BY M F O n Vl t;

ATTORNEY Nov. 8, 1966 J. G. HUGHES 3,283,991

RECLOSABLE CARTONS Filed Nov. 9, 1964 2 Sheets-Sheet 2 INVENTOR JOHN G. Hue/15s ATTORNEY United States Patent 3,283,991 RECLOSABLE CARTONS John G. Hughes, St. Paul, Minn., assignor to Waldorf Paper Products Company, St. Paul, Minn., a corporation of Minnesota Filed Nov. 9, 1964, Ser. No. 409,685 7 Claims. (Cl. 229-51) This invention relates to an improvement in reclosable cartons and deals particularly with a carton which is securely closed during transportation and which may be readily opened and reclosed to provide a securely locked carton in reclosed position.

Many cartons have been produced having a tray-like bottom portion, and a top hinged to the upper edge of the rear wall and including a top panel, and depending interconnected front and side wall flanges connected to the edges of the top panel. A locking flange is provided on the upper edge of the front wall folded down inwardly of the front cover flange, and an additional locking flange is hinged to the lower edge of the front cover flange to extend up inwardly of the front cover flange. These two flanges are designed to engage in edge-abutting relation to hold the carton closed.

In certain of these prior constructions, the locking flanges are adhered in face contact with the panels to which they are hinged. Such locks are relatively ineffective, as the flange edges do not engage if the front cover flange bulges, as it normally tends to. In other structures, one locking flange is adhered to the panel to which it i hinged, and the other locking flange is left unattached so that it may fold toward the abutting edge of the adhered flange. This type of lock is much more effective than that previously described. Perhaps the greatest difliculty with locks of this type lies in the fact that the front cover flange has a natural tendency to bulge or bow outwardly away from the front panel of the carton intermediate its ends. As a result, the two locking edges engage in edge abutting relation only at the ends of the flanges.

It has been found that if the flanges are formed so that the central portions of the flanges engage in edge-abutting relation, a superior lock is provided. Furthermore, such a construction may be more readily manually unlocked, as the locking edges may be disengaged by pressing inwardly on the front panel of the carton just below the lower edge of the front cover flange. Thus while the carton is more securely locked in closed position than other cartons of this type, the lock may also be more readily disengaged when it is desired to open the carton.

A feature of the present invention lies in the provision of a structure which actually takes advantage of the natural tendency for the front cover flange to bulge, thereby changing the natural disadvantage into an advantage. This is accomplished by providing a front cover locking flange hinged to the lower edge of the front cover flange and folded inwardly of the front cover flange, and adhering this locking flange to the inner surface of the front cover flange only at its upper extremity. This locking flange is longitudinally slit intermediate its upper and lower edges, usually throughout a major portion of the length of the locking flange. The slit is located below the area of the locking flange which is adhered to the front cover flange. As a result, the normal tendency for the locking flange to fold back into the plane of the front cover flange to which it is hinged provides a natural tendency for the area of the locking flange below the slit to bulge inwardly toward the front container wall. By providing an abutment on the front wall against which the unsecured edge of the slit may engage, a very positive lock is provided.

Patented Nov. 8, 1966 A further feature of the present invention lies in the fact that the lock is more effectively controlled than in previous structures in which the locking flange is free to fold about a fold line. For example, if the unadhered locking flange is hinged to the upper edge of the front carton panel, this locking flange is folded upwardly as the carton is opened. If this locking flange is not returned to its original position during the closing of the cover, the lock is inoperative. This is also true if the locking flange is hinged to the lower edge of the front cover flange; if this type of lock functions, there is a tendency for the unadhered locking flange to fold downwardly as the cover is opened. The lock will then not function unless the locking flange is folded back into its original position during the closing of the carton.

A further feature of the present invention lies in the fact that the lock may be more effectively disengaged manually when it is desired to do so. As the slit extends a major portion of the length of the lock-ing flange, the lower edge of the slit engages the abutment on the front wall panel for a considerable distance on each side of the center of the slit but the locking edge terminates short of the corners of the carton. In previous constructions, Where the unadhered locking flange was free to fold throughout its length, the locking flange functioned most effectively near the ends thereof, or near the corners of the carton. As a result, forcing the front carton panel inwardly did not disengage the locking flange from the abutment. However, with the present structure, flexing the center portion of the front panel inwardly is much more effective in disengaging the lock.

These and other objects and novel features of the present invention will be more clearly and fully set forth in the following specification and claims.

In the drawings forming a part of the specification:

FIGURE 1 is a perspective view of the carton in closed condition.

FIGURE 2 is a perspective view of the carton with the cover swung into open position.

FIGURE 3 is an enlarged sectional view through a portion of the carton, the position of the section being indicated by the line 3-3 of FIGURE 1.

FIGURE 4 is a view similar to FIGURE 3, but showing the cover in partially opened position.

FIGURE 5 is a diagrammatic view of the blank from which the carton is formed.

FIGURE 6 is a diagrammatic plan view of the blank after the first folding operation.

FIGURE 7 is a diagrammatic plan view of the blank in completely folded relation.

FIGURE 8 is a diagrammatic view of a partial blank showing a modified form of construction.

The carton A is formed of the blank illustrated in plan in FIGURE 5 of the drawings. As indicated, the blank includes a front wall panel 10, bottom panel 11, a rear wall panel 12, and a top wall panel 13, connected along parallel fold lines 14, 15, and 16. End closure flaps are hingedly connected to the various wall panels along parallel fold lines 17 and 19 which intersect the previousy described fold lines, usually at right angles. The end closure flaps include front wall flaps 20 hinged to the front wall 10, and rear wall flaps 21 hinged to the edges of the rear panel 12. The combined length of the flaps 20 and 21 is preferably substantially equal to the width of the bottom panel 11, so that when the flaps 20 and 21 are folded into common planes at opposite ends of the carton, the end edges of the flaps will be in substantially edge-abutting relation.

Top panel closure flaps 22 are foldably connected to the top panel 13 along the fold lines 17 and 19. Weakened lines of separation 23 extend across the flaps 22 in generally parallel relation to the fold lines 17 and 19, dividing the top wall closure flaps 22 into lower anchoring portions 24 and upper cover flanges 25 between the weakened lines 23 and the adjoining fold lines 17 and 19. The bottom panel 11 is provided with closure flaps 26 which. in the arrangement illustrated, overlap the lower anchoring portions 24 of the top wall closure flaps 22 and are adhered thereto in face contact.

A cover front wall 27 is hingedly connected to the forward edge of the top panel 13 along a fold line 29 which is parallel to the fold lines 14, 15, and 16. A front locking flange 30 is foldably connected to the lower edge of the front cover wall 27 along a fold line 31. An abutment-forming flange 32 is connected to the edge of the locking flange 30 along a weakened line 33. The locking flange 30 is of approximately the same length as the front cover wall 27 and lies inwardly thereof in completed form of the carton. A slit 34 is provided in the locking flange 30 extending the major portion of the length thereof, terminating short of the vertical edges of the flange 30 preferably angled toward the weakened line 33 as indicated at 35, the slit 34 and its ends 35 forming a shallow generally U-shaped cut. The distance between the slit 34- and the fold line 31 is slightly in excess of the vertical length of the abutment flange 32 for a purpose which will be later described.

Corner-connecting flaps 37 are hingedly connected to the side edges of the front cover wall 27 along extensions of the fold lines 17 and 19. The front cover Wall 27 is of a length approximately equal to the vertical length of the cover side wall flanges 25 forming a part of the clossure'flaps 22. When the carton is opened, the top or cover panel 13 is reinforced along three edges by the cover front wall 27 and the cover side flanges 25 which are secured in right angular relation by the corner flaps 37.

In the formation of the carton A from the blank illustrated in FIGURE of the drawings, the blank is folded along the fold line so that the bottom panel 11 and front wall panel 10 overlie the rear wall panel 12 and top panel 13, respectively. Adhesive is next applied to the abutment forming flange 32 and to the area of the liner flange 30 which is between the slit 34 and the fold line 33. The blank is then folded along the fold line 31 so that the abutment forming flange 32 overlaps the marginal edge of the front panel 10, the adhesive being between the abutment forming flange 32 and the fiont panel 10. This operation also folds the front wall locking flange 30 into face contact with the front cover wall 27.

Preferably while the adhesive is still moist, the blank is then folded along the fold line 29. This action folds the blank from the position stated in FIGURE 6 of the drawings to the position shown in FIGURE 7. As shown in FIGURE 7, the front cover wall 27, the locking flange 36, and the abutment forming flange 32 are all in position overlying the marginal portion of the front panel and the corner flaps 37 overlie the closure flaps on the front panel 10. The ends of the carton are preferably folded by folding the closure flaps 20 and 21 on the front and rear walls 10 and 12 inwardly into a common plane, and simultaneously folding the corner flaps 37 to lie outwardly of the closure flaps 20. The closure flaps 22 on the top panel 13 are next folded downwardly to overlie portions of the closure flaps 21, the cover side flanges forming a part of theclosure flaps 22 and being adhered to the outer surface of the corner flaps 37. The lower portions 24 of the cover flaps 22 may be adhered in face contact to the front and rear closure flaps 20 and 21. The bottom closure flaps 26 on the bottom wall 17 are folded into overlapping relation with the lower portion 24 of the top closure flaps 22 to complete the closing operation. When it is desired to open the carton, pressure is applied to the lower portions 24 of the top closure flaps 22, this action separating the closure flaps 22 along the weakened lines 23. Inward pressure may also be applied to the front wall 10 below the front cover Wall 27 and an upward pull is exerted upon the cover, causing the locking flange to split from the abutment forming flange 32 along the weakened line 33. This is simplified by the fact that the area of separation is along the top edge of the front panel. ened line 33, the cover may be swung open in the manner illustrated in FIGURE 2 of the drawings to disclose the carton contents.

When it is desired to reclose the carton, the cover panel 13 is merely swung closed. As this takes place, the portion of the locking flange 3%) which extends along the slit 34 engages the lower free edge 40 of the abutment forming flange 32, effectively locking the cover closed. The opening of the cover is simplified if the center portion of the front panel 10 is flexed inwardly to some extent as the cover is opened.

As the locking flap 30 is adhered to the inner surface of the front cover wall 27, the structure provides no freely foldable locking flange capable of swinging out of position when the cover is opened. At the same time, the area of the locking flange 30 between the slit 34 and the fold line 31 actually bows inwardly, due to the natural tendency for the locking flange to return to the plane of the front cover wall. In view of the fact that the locking flange 30 is partially adhered to the inner surface of the cover front wall 27, the proper lock of the carton is insured.

As an indication of the effectiveness of the operation, cartons constructed with cover front walls 27 are perhaps 8%" in width by l in height, or longitudinally slit with slits 34 about 5" in length and located about midway between the top and bottom edges. When cartons of this type were formed and closed in the manner described and were then opened, it was found that the portion of the locking flange 30 between the slit 34 and the fold line 31 bowed inwardly about 1 Thus the cover was effectively locked and cartons containing crackers or similar product could actually be dropped without the cover becoming unlocked. However, where it was possible to press the front wall 10 inwardly to some extent, the lock could be readily opened when desired.

The blank shown in FIGURE 8 of the drawings is identical to that previously described with the exception of the fact that an area of the locking flange between the slit and the line of connection between the locking flange and abutment flange is cut away or apertured. The main portion of the blank B is identical to the blank A. However, in the blank B the cover flange or flap 27 is hinged along the fold line 41 to a liner or locking flange 42, which in turn is hingedly connected to the glue flap abutment flange 43 along a weakened line of separation 44. A generally rectangular aperture 45 is provided in the locking flange 42 extending from the location of the slit 34 of the blank A to the weakened line of separation 44. In this construction the cut edge 46 of the aperture 45 functions in the same manner as the edge of the slit 34 of the blank A to engage against the abutment flange 43.

In accordance with the patent statutes, I have described the principles of construction and operation of my reclosable carton; and while I have endeavored to set forth the best embodiment thereof, I desire to have it understood that obvious changes may be made within the scope of the following claims without departing from the spirit of my invention.

I claim:

-1. A reclosable cart-on including:

a body portion including a rectangular bottom panel, front, rear, and end walls hinged marginally to said bottom panel and extending upwardly therefrom, and means connecting said walls in rectangular relation,

a cover poantion hinged to the upper edge of said rear wall and including a top panel, a front cover flap hinged to said top panel along a fold line parallel to the fold line connecting said cover to said rear wall,

By splitting the weak- 

1. A RECLOSABLE CARTON INCLUDING: A BODY PORTION INCLUDING A RECTANGULAR BOTTOM PANEL, FRONT, REAR, AND END WALLS HINGED MARGINALLY TO SAID BOTTOM PANEL AND EXTENDING UPWARDLY THEREFROM, AND MEANS CONNECTING SAID WALLS IN RECTANGULAR RELATION, A COVER PORTION HINGED TO THE UPPER EDGE OF SAID REAR WALL AND INCLUDING A TOP PANEL, A FRONT COVER FLAP HINGED TO SAID TOP PANEL ALONG A FOLD LINE PARALLEL TO THE FOLD LINE CONNECTING SAID COVER TO SAID REAR WALL, END COVER FLAPS HINGED TO THE END EDGES OF SAID TOP PANEL, AND CORNER FLAPS HOLDING SAID FRONT COVER FLAPS AND SAID END COVER FLAPS IN RIGHT ANGULAR RELATION OVERLAPPING THE FRONT WALL AND END WALLS OF SAID BODY PORTION AND OUTWARDLY THEREOF, A LOCKING FLANGE HINGED TO THE LOWER EDGE OF SAID FRONT COVER FLAP AND FOLDED INWARDLY THEREOF, SAID LOCKING FLANGE HAVING A CUT LINE FORMING A CUT EDGE EXTENDING ACROSS THE CENTER PORTION OF SAID FLANGE AND TERMINATING SHORT OF THE END EDGES OF SAID FLANGE, THE AREA OF SAID FLANGE BETWEEN SAID CUT EDGE AND THE EDGE OF SAID FLANGE HINGED TO SAID FRONT COVER FLAP BEING FREE OF DIRECT ATTACHMENT TO THE INNER SURFACE OF SAID FRONT COVER FLAP AND FREE TO BOW INWARDLY TOWARD SAID FRONT WALL IN CLOSED POSITION OF SAID COVER PORTION, SAID FLANGE INCLUDING AN AREA EXTENDING BEYOND SAID CUT EDGE IN A DIRECTION TOWARD THE LINE OF FOLD CONNECTING SAID FRONT COVER FLAP TO SAID COVER PANEL, MEANS ATTACHING SAID AREA OF SAID FLANGE IN FACE CONTACT WITH SAID FRONT COVER FLAP, AND AN ABUTMENT FLANGE SECURED IN FACE CONTACT WITH OUTER SURFACE OF SAID FRONT WALL ALONG THE UPPER EDGE AND ABOVE SAID CUT EDGE OF SAID FLANGE IN CLOSED POSITION OF SAID COVER, SAID ABUTMENT FLANGE HAVING AN EDGE PROVIDING A SHOULDER AGAINST WHICH THE CUT EDGE OF SAID FLANGE MAY LOCK IN CLOSED POSITION OF SAID COVER PORTION. 